QUESTION $3$

Gas and liquid flow through a horizontal pipeline at a volumetric flow rate of $0\mathrm{.}5\frac{m^3}{s}$ and $0\mathrm{.}05\frac{m^3}{s}$ respectively. The internal diameter of the pipe is $20cm.$ Estimate the pressure gradient. The following physical properties are available ${}_G=0\mathrm{.}756k\frac{g}{m^3}$; ${}_G=1\mathrm{.}05{10}^{-4}$ Pa$.$s and ${}_L=850k\frac{g}{m^3}$;${}_L=8\mathrm{.}95{10}^{-4}$ Pa$.$s$.$ The moody friction factor is $0\mathrm{.}018.$

$[10]$